Clip for clothing strips

ABSTRACT

The invention relates to fastening means (in particular to so called clothing clips) for the fastening of clothing strips on flat rods, made of light metal or light metal alloys. Thereby the fastening means are laid-out in such a manner that, when the flat rods assume their operating temperature, these are not deformed.

RELATED APPLICATION

The present application is a Divisional Application of U.S. applicationSer. No. 10/468,747 with a filing/§ 371 date of Mar. 3, 2004.

BACKGROUND OF THE INVENTION

The present invention relates to fastening means, in particular topositive connecting means, as for example clips for fastening ofclothing strips to flat rods.

Modern textile processing machines, in particular, cards are furnishedwith different carding segments, depending on the process stage.Stationary carding segments and/or carding rods to the carding segmentsof the card belong, in particular, in the pre-carding and re-cardingzone and the carding segments. Most cards nowadays are furnished withrevolving flat aggregates, i.e., they possess revolving flat rods. Cardswith stationary flats and, respective, stationary flat rods are lesscommon. With cards, it is common to furnish the flat or revolving flatrods with so-called clothing strips. The clothing strips are furnishedwith flexible or semi-rigid clothing, which differ from all steelclothing and/or saw tooth type clothing in such a way, that they areinserted and/or punched individually, or as U-shaped double hooks, intomore or less flexible fabric and plastic layers.

The clothing strips are attached with fastening means, so-called clipsor clothing strip clips, to the carding rods of the carding segments.Various clips of the state of the art are shown, for example, in thedisclosures U.S. Pat. No. 5,755,012, U.S. Pat. No. 5,898,978 and DE513728. Such an arrangement is, for example, also shown in FIG. 1. Theclips 1 are made of sheet metal and/or steel and they advantageouslysimplify the fastening and replacing of the clothing strips 2 onto theflat rods 3. The clips 1 have the function of fixedly clamping theclothing strips 2 onto the flat rods. They do this by establishing apositive connection between the clothing strip and the flat rod.Normally, the clips are employed in pairs, so that a clip is to ensurefor respective clamping on both sides of the flat rod (see FIG. 1). Onone side, the clips have teeth 4. These teeth 4 are inserted and/orpunched into the clothing strips 2 (illustrated in FIG. 1 with a brokenline). Thereby, these teeth 4 are positively connected with the clothingstrip. The other side 5 of the clips is pressed around the rib 6 of theflat rod 3 by applying a suitable tool. Thus, the clips 1 firmly clampthe clothing strips 2 to the flat rod 3 over its entire length. Thistype of fastening has proved successful in the past. The clips can beattached very easily to the flat rods with a suitable tool and can alsobe easily removed again.

The carding rods, and in particular the flat rods for the card, wereformerly manufactured in the form of a—usually T-shaped—cast iron.Recently they have also been manufactured in the form of hollow profiles(extruded profiles) of light metal and/or light metal alloys (e.g., flatrod 3 in FIG. 1). Aluminum is often used as a material for theproduction. The carding segments co-operate with rotary rollers, as dothe flat rods, which co-operate with the cylinder of the card. Thereby,the carding rods or flat rods must be somewhat longer than the workingwidth of the card, so that they can rest on the adjustable flex bends onthe left and on the right side of the cylinder and can be transported(or, in the case of stationary flat rods, be fastened thereon). The flatrods are exposed to a relatively high mechanical load (shearing load)applied through their carding work. Therefore, they must have a highstability or rigidity, in order not to deflect or deform duringoperation.

The carding quality, and thus the quality of the produced card web,depends substantially on the set carding gap (space between the clothingof the flat rods and the clothing of the cylinders). This carding gap isnowadays adjusted within the range of tenth of millimeters. Usually, itmeasures between 0.2 and 0.3 mm, depending on the processed fibrematerial and the desired carding quality. It can be observed that thetendency in the spinning mills points in the direction of setting oradjusting the carding gap within ever more narrow ranges. Carding gapsettings of 0.15 mm represent at the present the rather extreme case,however, such narrow settings might be wished in the future morefrequently by spinning mills. Therefore, the accurate setting of thecarding gap is very important. It is, therefore, understood thatfluctuations and inaccuracies in the adjusted space have considerablenegative effects on the quality of the carding process. For the cardingprocess it is very important that the carding gap over the entire workarea within which carding work is done can be adjusted evenly. Forexample, the carding gap must be accurately adjusted over the totallength of the flat rods and over the whole area of the flat (i.e.,within the work area of all flat rods being arranged one behind theother). The narrower, however, the carding gap is chosen, the moredifficult it is to adjust it and to keep it constant. The narrower therange gets within which the carding gap is to be kept, the moresensitive the flat area reacts, with the set carding gap, to each effectand to each change, like for example temperature fluctuations. Thecarding gap is adjusted and/or checked during standstill with a feelergauge. Usually this setting takes place once in each case after eachadjustment of the flats of the card, for example, after maintenance (thereplacement of the flats) or in the case of a change of the processedmaterial (fiber material to be treated newly often requires anothercarding gap adjustment). Adjusting of the flats actually always takesplace on the “cold machine”, i.e. at normal ambient temperature, whichcan differ, depending on the location of the machine within the spinningmill, between 20 and 30 degrees Celsius. During operation of the card,the operating temperatures at the flat rods, depending on the airconditioning, can amount to between 20 degrees Celsius (during startingperiod of the machine) and 40 degrees Celsius (with a warm machine andbad air conditioning within the spinning mill). It is understood thatthe carding gap, even with such temperature fluctuations, is always tobe held at the desired value. However, the narrower the carding gapneeds to be adjusted, the more sensitive is the reactions of the cardingprocess to changes of the gap.

Recently, the flat rods have been made of light metal, in particular ofaluminum, and/or of light metal alloys as extruded hollow profiles,produced by extrusion method (see FIG. 1). Such flat rods are providedwith solid headpieces at their two ends. Examples of such flat rods canbe seen in the disclosures DE 43 04 148 A1, EP 627,507 B1 or U.S. Pat.No. 4,827,573. The headpieces are usually positively connected with thealuminum profile and have a machined bearing surface, which slidesaccurately and with low friction on the sliding guides of the card (flexbends). In the case of revolving flat rods, the headpieces arefurthermore connected with the drive components of the flat aggregate,e.g., with a driving chain or a driving belt. This design has a numberof advantages in comparison to the older type flat rods made as casting.In particular, they can be manufactured more simply and cheaper.

The use of light metal or light metal alloys as material for the flatrods can, however,—under certain operating conditions—also havedisadvantages. With such types of flat rods up to now, common type clipsmade of sheet metal or steel were used. Measurements now revealed thatthese flat rods can deform when the temperature rises to the operatingtemperature in the card. The reason for this is that the clips aremounted onto the flat rods at room temperature. In the case of atemperature rise of the card to the operating temperature, the mountedflat rods resume a concave type of shape seen in their longitudinaldirection, so that the carding gap is larger in the center of the flatrod than at its end. Thus, the carding process can be impaired. Theimpairment of the carding process is the more serious the narrower thecarding gap is set and the longer the flat rods are. With the cardinggap settings applied nowadays, it should therefore be avoided that theflat rods become bent.

OBJECTS AND SUMMARY OF THE INVENTION

Therefore, a principal object of the present invention is thus to avoidthe deformation of the flat rods. Additional objects and advantages ofthe invention will be set forth in part in the following description, ormay be obvious from the description, or may be learned through practiceof the invention.

The light metal or the light metal alloy of the flat rods has a highercoefficient of elongation and/or coefficient of thermal expansion thanthe sheet metal and/or the steel from which the clip is made. Thecommercially available clips thus consist of a material (sheet metal orsteel) that has a too high E-modulus for flat rods made of light metal,i.e., they have a low flexibility. They are, in particular, far lessflexible than the flat rods. In addition, the clips, apart from thematerial properties, also have (primarily due to the selected wallthickness) a high rigidity due to the design. In the mounted condition,the clips have a high clamping force and are, practically seen,inelastic. The wall thickness of commercially available clips amounts toat least 0.5 mm. The clothing strips are positively connected(“clipped-on”) onto the flat rod at room temperature with the help ofthe clips and a suitable tool. Afterwards the flat rods are examined fortheir accuracy with regard to the clothing. If necessary, the clothingpoints are reground (by a few hundredths of a millimeter), so that thegap between the sliding surfaces of the head pieces of the flat and thearea defined by the clothing points resume an accurate predeterminedvalue. This examination is accomplished in the spinning mills at ambienttemperature and is made in order to precisely adjust the carding gap.The flat rods with the attached clips and clothing strips aresubsequently mounted into the card, at which point they have the ambienttemperature. If the card becomes warm through its operation, then alsothe flat rods warm-up. Consequently, the flat rods expand (or try toexpand). The problem, thereby, is that the flat rod has, due to thematerial type (light metal or a respective alloy), a higher coefficientof thermal expansion than the clip (commercially made of sheet metal orsteel). Besides, the clip has, due to the applied material, a highE-modulus (low elasticity), which is additionally reinforced due to itsdesign (wall thickness). The result is a high strength connected with avery low elasticity (at least a lower elasticity than the flat rod). Thepositive connection of the clips (at least two clips per flat rod arerequired for the fastening) with the flat rod within the area of theribs 6 (see FIG. 1) has a high clamping force. It is so high that norelative motion can take place at these points between the flat rod andthe strip. In particular, the material with the higher coefficient ofelongation cannot expand. Consequently, the lower thermal expansion ofthe clips prevents the flat rod from expanding within the clampedsection 7 in the same way in longitudinal direction as within the uppernon-clamped section 8 of the flat rod, where no obstacle prevents thethermal expansion. The arc-shaped bend of the flat rod resulting fromthis causes an undesired, non-uniform carding gap over the length of thecarding flat. Particularly, with narrow settings, where the carding gapis to amount to between 0.2 to 0.15 mm, then this effect is particularlynegative.

According to the general idea of the invention, it is to be avoided thatthe flat rod, due to the fastening device, i.e., the clip, is preventedfrom expanding evenly. This idea can be realized by differentembodiments according to the invention.

According to a first embodiment of the invention, the fastening devicesare made of a material that possesses the same coefficient of elongationas the flat rod. In a particularly preferred embodiment, the fasteningdevices are made of, thereby, also at the same time, of the samematerial as the flat rod. According to this embodiment of the invention,it is essential that light metal flat rods are being used in combinationwith the fastening devices (clothing clips), which, according to theinvention, comprise the same (or nearly the same) materialcharacteristics.

This first embodiment according to the invention refers to flat rodsthat are not manufactured of steel or cast iron. It refers, inparticular, to flat rods that are manufactured of a light metal or alight metal alloy, in particular, aluminum or an aluminum alloy.

In a second embodiment according to the invention, fastening devices forthe fastening of clothing strips on flat rods are used, which are madeof aluminum, or aluminum alloy, or another light metal or light metalalloy. This second embodiment according to the invention is concernedwith the selection of the material from which the fastening devices aremade. In a secondary embodiment the flat rods can be made of a lightmetal or a light metal alloy, in particular, they can be made ofaluminum or an aluminum alloy.

According to a third embodiment of the invention, fastening device forfastening the clothing strips on flat rods are applied that arecharacterized in that the fastening means are more flexible in theirlongitudinal direction than in their cross direction.

Such fastening means, or devices, can have such characteristics due totheir specific way of design.

These can be realized in particular in that they are designed withpredetermined weak points. Such predetermined weak points can berealized in such a manner that the fastening means, with regard to theirextension, have different values of elasticity.

In a fourth embodiment according to the invention, fastening devices forfastening the clothing strips on flat rods are applied that have a wallthickness which is smaller than 0.4 preferably smaller than 0.3 mm. Bythis design measure, it is in particular suitable to apply well knownmaterials for the fastening means, for example, sheet metal or steel.Due to the small cross-section and/or wall thickness, the fasteningmeans, despite an unchanged high E-modulus, is structurally weakened andtherefore less rigid. Thereby, the flat rod is given the possibility toexpand the fastening means, i.e., the clips, in a longitudinaldirection. In fact, the structural weakening reduces the clamping forceof the fastening means. The wall thickness however can be selected insuch a manner that the weakening does not critically affect the clampingforce.

A fifth embodiment according to the invention is characterized in that,between the contact surfaces of the fastening means, or device, and theflat rod, a sliding means is attached.

The sliding means is arranged in such a manner, that it permits thefastening means, as well as the flat rod, to move and/or expand in alongitudinal direction (i.e., along the flat rod) relative to the otherelement. This relative motion in the longitudinal direction takes placein particular when the temperature of the flat rod rises, so that thecomponent with the higher coefficient of elongation (e.g., the flat rod)can expand in the longitudinal direction unhindered from the othercomponent (e.g., fastening means). This basically means that thefastening means does not have to take part in this movement or expansionof the flat rod: The flat rod can expand unhindered, and, thus, notensions can develop, which could cause a bending of the components. Theclamping effect of the fastening means (transverse to the longitudinaldirection of the flat rod) does not become affected.

In a variation of this fifth embodiment, the sliding means between thecontact surfaces of fastening means and flat rod is realized as a glidelayer with a low coefficient of friction.

With this embodiment of the invention, the flat rod is preferably madeof a light metal or a light metal alloy. In particular, it is made ofaluminum or an aluminum alloy.

The object of the invention, which in all foregoing embodiments of theinvention is called “fastening means, or device” can also be a so-calledclip, in particular, for fastening of clothing strips onto flat rods(revolving flat or stationary flat rods) of the card. In addition, theclothing strips can be furnished with an allsteel clothing (saw toothtype clothing). The object of the invention is not limited to theapplication in flat rods of the card. It can also serve, in particular,as fastening means for other carding segments with other clothing types(carding segments of the card, such as those of other blow room machine,in particular, cleaners). The object of the invention is alsopreferentially suitable as a fastening means for carding segments withall steel clothing. The fastening means according to the invention cantherefore also be applied in other carding segments in the card or in acleaner of the blow room. Together, with the card go the cardingsegments in the pre-carding zone or re-carding zone of the cylinder, orthe carding segments at the licker-in. With cleaners, the fasteningmeans can be applied with stationary carding segments. If the fasteningmeans is a clip, then it can be made of sheet metal, preferably ofsteel.

If the sliding means between the contact surfaces of fastening means andflat rod is being realized as a gliding layer with a low coefficient offriction, then the gliding layer can be applied in the form of acoating, in particular, a plastic coating, on the fastening means and/oron the flat rod. The application of the coating can also take placelater. In a preferred embodiment, the coating is applied only on thecontact surfaces between the fastening means and the flat rod.

In a further preferred embodiment of the invention, the fastening devicehas teeth, which are stable enough to be entered or punched into thefabric and/or plastic layers of the clothing strips. This featureapplies in particular to fastening means which are not made of steel orsheet metal, but, for example, are made of aluminum or some othermaterial. Such fastening means according to the invention are, inparticular, suitable for the fastening of clothing strips on machinecomponents of the card.

For the fastening of the clothing strips on the flat ends preferably atleast two fastening means are applied according to the invention.

The present invention is further described in the following figures byways of examples.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a flat rod with clips according to the state of the knownart;

FIG. 2 shows a fastening means according to an embodiment of theinvention;

FIG. 3 shows a variation according to another embodiment of theinvention;

FIG. 4 shows a fastening means according to a further embodiment of theinvention with sliding means; and

FIG. 5 shows a further fastening means according to the invention.

DETAILED DESCRIPTION

Reference will now be made in detail to the presently preferredembodiments of the invention, one or more examples of which are shown inthe figures. Each example is provided to explain the invention and notas a limitation of the invention. In fact, features illustrated ordescribed as part of one embodiment can be used with another embodimentto yield still a further embodiment. It is intended that the presentinvention cover such modifications and variations.

The flat rod in FIG. 1 was already described further above. Therefore,there is no need for further explanation. The clips 1 are manufacturedof sheet metal or steel according to the state of the art and have awall thickness of 0.5 mm. The flat rod 3 is made of a light metal or alight metal alloy. This combination has the above-describeddisadvantages.

In FIG. 2, a fastening means, or device, according to an embodiment ofthe invention is shown (in two views). The fastening means 9 accordingto the invention is more flexible in its longitudinal direction 10 thanin its transverse direction 11. This characteristic was achieved at thefastening means 9 by way of its structural design. It has groove shapedpredetermined weak points 12 at regular spaces in its longitudinaldirection 10. The wall thickness is reduced at these points, so that thefastening means 9 has an overall reduced rigidity in longitudinaldirection 10 and thus a higher elasticity. By this structural design,the clamping force in cross direction 11 is hardly reduced and theelasticity of the fastening means 9 is only insignificantly increased.

The FIG. 3 shows a further variation of the embodiment in FIG. 2according to the invention, likewise in two views. Here also,predetermined weak points 12 in the form of punched material are workedinto the fastening means, or device, 13. Thus, the fastening meansreceive a direction-controlled elasticity and/or rigidity, and thus thefastening means 13 becomes lengthwise flexible. In cross direction 11,however, it keeps the required rigidity.

The FIG. 4 shows a flat rod 3.1 with a clothing strip 2, which isattached by two fastening means, or devices, 15 according to the furtherembodiment of the invention.

Between the contact surfaces of fastening means 15 and the flat rod 3.1sliding means 14 are attached. In this embodiment, the two fasteningmeans 15 also have teeth 4, which engage in the clothing strip 2 of thefabric layer. The sliding means 14 are here only to be understood asschematic illustrations. They permit the flat rod 3.1 and the fasteningmeans 15 to move relatively to each other (in viewing direction, i.e.,in a longitudinal direction of the flat rod 3.1), in particular toexpand relatively to each other at a temperature rise. As sliding means14, gliding layers could, for example, be applied, which have a lowcoefficient of friction. The sliding means 14 can be applied both on thefastening means 15 and/or on the flat rod 3.1. The sliding means 14 canonly be attached on the contact surfaces (as shown), or extend beyondone and/or the other component (fastening means 15 or flat rod 3.1)covering it entirely or partly (not shown). For example, the fasteningmeans 15 could be completely surrounded and/or coated by the slidingmeans 14. The illustrated sliding means 14 can also be a plastic coating(or a silicone layer).

The FIG. 5 shows a detail of a fastening means, or device, 16 accordingto the invention. Thereby the fastening means 16 is shown in twoconditions. The illustration on the left shows the fastening means 16 inthe unbent condition on which one sees in particular the teeth 4.

According to one design of an embodiment of the invention, the fasteningmeans 16 can comprise a wall thickness d, which is thinner than 0.4 mm,preferably thinner than 0.3 mm.

The illustration on the right shows the fastening means 16 in the formas it is applied in mounted condition (without flat rod or clothingstrip). One sees the way the teeth 4 are pointing upward. During anormal assembly, these are punched and/or pressed into the fabric layersof the clothing strip (see teeth of FIG. 4). The teeth 4 according tothe invention are designed in such a manner (e.g., by their form anddimensions) that they are stable enough in order to be engaged in thefabrics and/or plastic layers of the clothing strips.

The fastening means according to the invention are made of preferably ofa material, which possesses the same coefficient of elongation as lightmetal or light metal alloys, such as aluminum or aluminum alloys. Thefastening means are comprised in particular of a material, whichpossesses the same coefficient of elongation as the material of whichthe flat rods are manufactured, whereby these are preferably produced oflight metal or light metal alloys.

The invention also concerns the use of fastening means on the flat rods,made of light metal, for the fastening of clothing strips.

By the expression “fastening means, or device,” clips for the fasteningof clothing are to be understood in particular. This clothing could beflexible clothing, in particular, so-called clothing strips, but alsoallsteel clothing, e.g., saw tooth clothing. Preferably, the fasteningmeans according to the invention are applied for the flat rods of thecard. They are, however, not limited to this application. The fasteningmeans according to the invention can in particular also serve for thefastening of other carding segments, in particular for stationarycarding segments in the pre-carding zone and in the re-carding zone ofthe card, as well as its licker-in and at cleaners in the blow room. Thefastening means according to the invention can be used for example forapplications according to the disclosures CH 659,832, CH 654,341, CH655,521 in place of the conventional clips or clips described there, inparticular for holding allsteel clothing and so-called card clothing.

The invention is not limited to the possibilities and embodimentsexplicitly being specified. These variations are rather meant assuggestions for the specialist for the realization of the idea of theinvention in a most favorable manner. From the described forms ofembodiments, therefore, further favorable applications and combinationsare easily derivable, which likewise reflect the idea of the inventionand which are to be protected by this application. It will beappreciated by those skilled in the art that various modifications andvariations can be made in the present invention without departing fromthe scope of the invention. It is intended that the present inventioninclude such modifications and variations as come within the scope ofthe appended claims and their equivalents.

1. An apparatus for the fastening of clothing strips on a flat rod, saidapparatus comprising a fastening device extending in a longitudinaldirection and a cross direction, said fastening device being moreflexible in said longitudinal direction than in said cross direction. 2.An apparatus as in claim 1, wherein said fastening device defines weakpoints within the fastening device.
 3. An apparatus as in claim 2,wherein said weak points are placed at predetermined locations on saidfastening device to give the fastening device different values ofelasticity in said longitudinal direction and said cross direction. 4.An apparatus as in claim 3, wherein said weak points are formed in saidfastening device by removal of material at said predetermined locationsfrom said fastening device.
 5. An apparatus as in claim 4, wherein saidmaterial is removed from said fastening device by a punch.
 6. Anapparatus as in claim 1, wherein said fastening device is a clip.
 7. Anapparatus as in claim 1, wherein said fastening device comprises teethfor inserting into at least one of fabric or plastic layers of aclothing strip.
 8. An apparatus as in claim 1, wherein the fasteningdevice is suitable for fastening of clothing strips onto mechanicalcomponents of a card.
 9. An apparatus as in claim 1, wherein at leasttwo fastening device are used to fasten said clothing strip onto saidflat rods.
 10. An apparatus for the fastening of clothing strips on aflat rod, said apparatus comprising a fastening device having a wallthickness that is less than 0.4 mm.
 11. An apparatus as in claim 10,wherein said wall thickness is less than 3.0 mm.
 12. An apparatus as inclaim 10, wherein said fastening device is a clip.
 13. An apparatus asin claim 10, wherein said fastening device comprises teeth for insertinginto at least one of fabric or plastic layers of a clothing strip. 14.An apparatus as in claim 10, wherein the fastening device is suitablefor fastening of clothing strips onto mechanical components of a card.15. An apparatus as in claim 10, wherein at least two fastening devicesare used to fasten said clothing strip onto said flat rods.
 16. Anapparatus for the positive fastening of clothing strips on a flat rod,said apparatus comprising: a fastening means for holding said clothingstrips on a flat rod; and a sliding means applied between said flat rodand said fastening means where said fastening means contacts said flatrod.
 17. An apparatus as in claim 16, wherein said sliding means allowssaid fastening means and said flat rod to move relative to one anotherwhen a temperature rise occurs.
 18. An apparatus as in claim 16, whereinsaid sliding means comprises a gliding layer with a low coefficient offriction.
 19. An apparatus as in claim 18, wherein said gliding layercomprises a coating applied to at least one of said fastening means orsaid flat rod.
 20. An apparatus as in claim 19, wherein said coating isa plastic coating.
 21. An apparatus as in claim 19, wherein said coatingis applied only to surfaces of at least one of said fastening means orsaid flat rods where said fastening means and said flat rods contact.22. An apparatus as in claim 16, wherein said fastening means is a clip.23. An apparatus as in claim 16, wherein said fastening means comprisesteeth for inserting into at least one of fabric or plastic layers of aclothing strip.
 24. An apparatus as in claim 16, wherein the fasteningmeans is suitable for fastening of clothing strips onto mechanicalcomponents of a card.
 25. An apparatus as in claim 16, wherein at leasttwo fastening means are used to fasten said clothing strip onto saidflat rod.
 26. An apparatus as in claim 16, wherein said flat rod iscomprised of at least one of a light metal or a light metal alloy. 27.An apparatus as in claim 16, wherein said flat rod is comprised of atleast one of aluminum or an aluminum alloy.